Ministers will discuss the Gatwick Airport drone drama in a Christmas Eve conference call as detectives examine a damaged drone in a bid to catch the culprits.
Sussex Police insisted they are “not back to square one”, despite releasing the two prime suspects initially held.
They said they were working with witness accounts and had forensic teams examining a damaged drone that was found near a runway.
Detectives hunting the Gatwick Airport drone operator are not ruling out the possibility that no drone activity took place.
Detective Chief Superintendent Jason Tingley added there was no available footage of the drones.
Police said there were some “persons of interest” after a damaged drone was found inside the airport’s perimeter fence. It follows the decision to release a man and a woman from nearby Crawley without charge.
The released suspects, aged 47 and 54, made no comment as they darted inside their home on Sunday morning, having been arrested on Friday evening following a “tip-off” from a member of the public.
Tingley said: “We are not back to square one. Whilst these two people have been in custody, we have a number of lines of inquiry and persons of interest.”
Asked about speculation there was never a drone, he said: “Of course, that’s a possibility. We are working with human beings saying they have seen something.
We are not back to square one…we are working with human beings saying they have seen something
Detective Chief Superintendent Jason Tingley
“Until we’ve got more clarity around what they’ve said, the detail – the time, place, direction of travel, all those types of things – and that’s a big task.”
But he said one of the “working theories” was that the damaged drone found close to the airport in Horley was responsible for causing the disruption.
He said: “Always look at it with an open mind, but actually it’s very basic common sense that a damaged drone, which may have not been there at a particular point in time has now been seen by an occupier, a member of the public, and then they’ve told us, ‘We’ve found this’.
“Then we go and forensically recover it and do everything we can at that location to try and get a bit more information.”
Around 1,000 flights were cancelled or diverted after drones were spotted inside the perimeter of the UK’s second biggest airport on Wednesday and approximately 140,000 passengers were affected.
Tingley said police were running a three-pronged investigation including working through information relating to “persons of interest”, investigating more than 67 drone sightings and forensically examining the damaged drone.
But he explained the examination could be hampered by the wet weather on Friday and Saturday, which could have washed away evidence.
And he could not rule out the risk the culprits would strike again at Gatwick or another airport.
But Tingley said he hoped the reward money – £50,000 from Crimestoppers and an additional £10,000 from the charity’s chairman Lord Ashcroft – would persuade someone to come forward with the vital clue.
“Someone, somewhere knows either the perpetrator or perpetrators responsible for this, or has information relating to these incidents,” he said.
“But secondly, our tactical response, should there be any more drone sightings, is still in place.”